Tag Archive: Human Genome Project

Continuing with our exploration of the vignettes in Science’s 10th anniversary celebration of the human genome project, we run across an interview with Eric Green, who just recently became the director of the National Human Genome Research Institute. As with all of these pieces, there’s lots of interesting stuff here. A couple of highlights from the interview:

Q: Why did you set 2020 for when genomics will begin affecting health care? Why is it going to take so long?

Eric Green: When we talk to people who have a historic view of medical advances, they have pointed out that truly changing medical care takes a substantial amount of time. Often decades. And I’ve grown sensitive to the criticisms of genomics by some who believe that since 2003, when the genome project ended, we haven’t sufficiently improved human health 7 years later. So part of the reason is just to be a little bit more realistic and a little more cautious.

Q: Where are you hoping we will be by 2020?

Eric Green: I’m hoping that by 2020 we will have this incredible mountain of information about how genetic variants play a role in disease, that it will just provide an entirely new venue for really thinking about how to both predict disease, maybe prevent disease, and certainly treat disease.

Notice that Dr. Green seems pretty confident in our ability to use genomics to predict and treat disease, but puts a “maybe” in front of prevention.

We’re starting to go through some of the interesting vignettes in Science’s 10th anniversary celebration of the human genome project. One of these papers takes a realistic view of how genomic research has benefited human health over the past 10 years. A few areas that the authors touch on:

1. Identifying risk: The predictive power of most genetic variants associated with diseases is not very high. This means that the potential benefits of separating patients even into gross categories such as “high” and “low” risk based on the presence/absence of disease-risk genes are in many cases outweighed by the cost of potentially misclassifying (and thus mistreating) them.

2. The difficulty of changing behavior: When someone is told they are at a genetically higher risk of developing a particular disease, there is really no evidence to indicate that they change their dietary or exercise habits (see also this post on the blog). Altering an individual’s environment (regardless of the presence/absence of disease-risk genes) is probably a better, and more lasting, way of convincing them to be less lazy, or to eat better and not smoke.

3. False hope: Scientists and the press are both responsible for creating false hopes for genomic research in human health.

The authors do suggest that the following are realistic expectations:

1. The genes responsible for most Mendelian disorders will be identified. This will permit quick diagnoses, particularly for diseases that are caused by a single gene.

2. Pharmacogenomics (the study of the influence of genetic variation on drug response) will enhance the safety and efficacy of treatments. However, because a lot of variability in drug response is tied to non-genetic factors, we can’t expect genomics to completely solve this issue.

They make the interesting suggestion that because most mortality in high-income countries results from things like smoking, sedentary behavior, and excessive food and alcohol consumption, the diseases associated with these factors are best (or at least as effectively) researched via the social and behavioral sciences (i.e., how do we change these behaviors?) rather than through genomics (i.e., how do we identify individuals at genetic risk for these diseases?).

It was waaaaaaayyy back in Feburary, 2001, when the human genome sequence was first published in the journal Science. This month, Science is running a series of vignettes about the impact of this revolution on genetics, culture, society, policy, and everything else. Take some time and look them over.

Discover Magazine recently posted an interesting interview with Leroy Hood, who invented the automated DNA sequencer (among other things) and was a key player in the Human Genome Project. He has since founded the Institute for Systems Biology, which is a non-profit research center focused on understanding how genes and proteins function in complete biological systems.

There is a lot of provocative stuff here, but we’ll just quote one of Dr. Hood’s more interesting predictions. When asked about his claim that medicine is on the edge of an ‘information revolution’:

In less than a decade, each of us will be surrounded by a virtual cloud of billions of points of medical data. Genome sequencing will cost only a few hundred dollars, so that will become a part of the medical record of each individual. A fraction of a drop of blood will be used to measure 2,500 blood proteins that assess the possibility of disease in each of your 50 major organs. Medicine will be personalized and preventive: Your genome might predict that you have an 80 percent chance of breast cancer by the time you are 50, but if you take a preventive drug starting when you are 40, the chance will drop to 2 percent. We will have the computational tools to connect all this information so we can gain enormous insights into health and disease and fashion an unbelievably predictive medicine of the future.

Last month, Diane Rehm of NPR had an interesting dicussion on DNA sequencing and personal genomics (you can listen to the 51-minute show in its entirety here). The completion of the human genome project in 2003 held the promise of using an individual’s genetic information to optimize their treatment. One example that the show uses is that of Google co-founder Sergey Brin, who has discovered that he possesses a mutation in his LRRK2 gene that may increase the likelihood of him developing Parkinson’s disease later in life. Nevertheless, the program’s guests demonstrate that there are still significant hurdles to truly effective genetic-based “personalized medicine.” A couple of interesting points from the show:

1. The cost of genome sequencing has declined greatly over the past decade or so. Some companies, like 23andMe (which was founded by Brin’s wife Anne Wojcicki) will sequence parts of your genome for about $500. For those of you interested in getting your entire genome (all 3 billion base pairs) sequenced, you can, with the consent of your doctor, send samples to companies like Illumina for the bargain price of about $20,000 (if you think that’s a bit pricey, consider that a decade ago it would have cost you about $1,000,000).

2. One of the guests, Dr. Arthur Caplan, provides examples of how people can react to genetic information. The most striking is the case where a father wanted to have his 13-year-old daughter tested for mutations associated with breast cancer risk (the family had a history of the disease). The father stated that if his daughter tested positive for one or more of the mutations, he would have her breast buds surgically removed to make sure that she did not suffer the same fate as other family members (Dr. Caplan does not tell us what ultimately happened with this case). One of the points that Dr. Caplan makes with this and other examples is that, although genetic screening can provide useful information, external environmental factors interact with genes in very complex ways, which currently makes it very difficult to assess an individual’s chances of developing conditions like cancer based simply on the presence or absence of particular genetic mutations (but see Personalized medicine in 10 years?).

3. All three of the guests discuss the issues surrounding genetic privacy. Once you submit samples for genetic sequencing, how can you be sure that your information will be kept private? If it is not kept private, what can it be used for? The importance of this issue is revealed by the signing of the Genetic Information Non-discrimination Act (GINA) by president Bush in 2008, which prevents discrimination based on genetic information when it comes to insurance and/or employment.

Check out the show and hit us up with your comments: Would you want your genome to be publicly available? Would you even want to know what your genome looked like? If you had the information, what would you do with it?